CNN — (CNN) -- Thousands of Ontario, Canada, residents made do without power Monday in the aftermath of storms that toppled trees and brought down power lines. Meanwhile, residents in the upper Midwest prepared for bitter cold wind chills.
More than 300,000 customers remained without electricity Monday across Ontario, including 200,000 in Toronto, officials reported, in the wake of what Mayor Rob Ford called one of the worst ice storms to hit the city.
Still, the city was functioning and conditions were "not even close" to warranting an emergency declaration, he told reporters Monday.
Toronto Hydro CEO Anthony Haines said major power lines are being restored at a rate of one every few minutes, but street-to-street work remains, and he couldn't offer a guarantee everyone will have power by Christmas.
"My caution continues to be my caution. Let's really plan for the worst," Haines said Monday evening. "I am encouraged in the progress we have made today, obviously, with well over 100,000 customers being restored today."
Ford said 100 trucks from other cities were on their way to Toronto to help restore power to more people.
Toronto had opened more than a dozen warming centers some were expecting up to 300 people, officials said.
In the United States, areas that had been as warm as the 70s on Sunday began a slide into frigid territory as Canada sent some of that cold air sliding across the eastern United States.
Dangerously cold wind chills were on tap in parts of Kansas, Nebraska, South Dakota, North Dakota, Minnesota, Iowa, Missouri and Illinois. Wind chill warnings were posted for parts of Minnesota, warning of of wind chills as low as 45 below zero.
Still, the picture was much calmer than over the weekend, when storms left at least 10 people dead.
At least five people died in Kentucky floodwaters, two people died in Mississippi storms, and one person died in a traffic accident during Missouri's severe weather, officials said. A weather-related wreck Saturday near Wichita, Kansas, left one person dead, according to CNN affiliate KWCH-TV. And a tornado Saturday also killed a woman in Arkansas, CNN affiliate KARK-TV in Little Rock reported.
The tornado was one of two rated at EF2 to hit the state on Saturday.
Northeast: Hot and cold
New York City set a record high Sunday at 71 degrees, National Weather Service meteorologist Ashley Sears said. The previous record, set in 1949 and matched in 1998, was 63.
But temperatures will fall each day until Wednesday, and by Christmas, New York might not even reach the freezing mark.
And in northern New England, another round of snow and ice is set for Monday, the National Weather Service said.
Southeast: When it rains, it pours
Rain was finally tapering off in Georgia, South Carolina and states in the Mid-Atlantic. A wave of cold temperatures will take its place Tuesday. Temperatures will likely be 10 to 15 degrees colder than normal on Christmas Eve and Christmas Day.
Midwest: Ice and dangerous wind chills
The storms left some Michigan residents dealing with no electricity. Sara Hadley's family lost power after an ice storm struck her hometown of Lansing. She sent photos of some of the countless icicles in her neighborhood.
"Last time we had ice like this was 1998," Hadley told CNN's iReport.
Pacific Northwest: Another storm brewing
Coastal and valley rain as well as mountain snow is in the forecast through Tuesday, the service said.
Higher elevations could get dumped with 6 to 12 inches of snow.
-- CNN's Sean Morris, Adam Shivers, Todd Borek, Jareen Imam, Leslie Holland and Janet DiGiacomo contributed to this report.
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